This invention relates to a structure for mounting a loudspeaker on an electronic musical instrument capable of freely adjusting the angle, adjusting the angle to vary the acoustic effect, and reducing the space necessary to accommodate the loudspeaker.
Various electronic musical instruments such as an electronic keyboard musical instrument, music synthesizer or the like are classified into two types, one containing the loudspeaker in the body of the musical instrument and the other in which the loudspeaker is separated from the body of the musical instrument.
Although the former enables compact the musical instrument, the sounds are confined in the instrument thereby degrading the sound quality or attenuating the sounds. When the sound volume is increased, the circuit board etc. vibrates thereby producing parastic vibration. Moreover, as high pitch tones propagate straightly, there is a limit to a position of which the loudspeaker can be mounted, thus decreasing the freedom of design.
The applicant has proposed an improved design for permitting the loudspeaker to be pulled out and pushed in for obviating this problem as disclosed in Japanese Preliminary Patent Publication No. 44888/1983. For example, a window is formed on the upper surface of the casing of an electronic musical instrument, and one end of a loudspeaker box having a sector shaped cross-section is hinged to one edge of the window so as to swing the box, whereby the loudspeaker box is pulled out or pushed into the casing.
With the method of mounting the loudspeaker, however, since the loudspeaker box is made to appear and disappear from the main body of the musical instrument a large space is necessary for the loudspeaker box, thus making it impossible to make small the musical instrument. Moreover, as the inner volume of the loudspeaker box is constant, it is impossible to change the sound effect as desired.